A short drink and a bad one (5)
I believe the answer is:
meths
'a short drink and a bad' is the definition.
I can't judge whether this definition defines the answer.
'one' is the wordplay.
I cannot quite understand how this works, but
'one' could be 'me' (a setter might use 'one' to humourously mean 'me') and 'me' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for meths that I've seen before include "Fuel" , "Methylated spirits (colloq.)" , "unsuitable alcohol" , "Violet-coloured alcohol" , "Spirit" .)